After reading this chapter, you should be able to:

1 Explain why researchers select samples that are representative of a population of interest.

2 Distinguish between subjects and participants as terms used to describe those who are subjected to procedures in a research study.

3 Distinguish between probability sampling methods and nonprobability sampling methods.

4 Delineate two nonprobability sampling methods: convenience sampling and quota sampling.

5 Delineate four probability sampling methods: simple random sampling, stratified random sampling, systematic sampling, and cluster sampling.

6 Define and explain sampling error and the standard error of the mean.

7 Define and explain sampling bias and nonresponse bias.

8 Identify potential ethical concerns related to sampling from “participant pools” in human participant research.

9 Compute an estimate for the standard error of the mean and compute the one-sample t test using SPSS.